Cannot execute connection script for Uno on Mac

Having a very similar issue to what was discussed here in a previous thread:

Tried the suggested fixes, including editing the connection and the chmod,

Still end up with this.

Last login: Sun Feb 18 03:42:31 on ttys000
Mac-mini-2:~ martylappin$ ./cayenne-ser.sh
-bash: ./cayenne-ser.sh: No such file or directory
Mac-mini-2:~ martylappin$ sudo ./cayenne-ser.sh
Password:
Sorry, try again.
Password:
sudo: ./cayenne-ser.sh: command not found
Mac-mini-2:~ martylappin$

Using a Arduino Uno on a Mac Mini running the newest OS update, using Safari.

Used the equivalent of a hammer to work around it. Went thru the script and changed everything required, then copied and pasted into terminal window.